The present invention relates to an exterior rearview mirror assembly for mounting on a vehicle and, more particularly, to a break-away exterior rearview mirror system which includes a movable portion that moves between a normal operating position, in which the occupant of the vehicle has a rearward field of view, and a folded, retracted position in which the mirror assembly is folded in toward the body of the vehicle when an external force is applied to the mirror assembly.
Conventional exterior rearview mirror assemblies include a housing with a reflective element supported in the housing and a mounting bracket for mounting to the vehicle. To minimize the damage to the exterior rearview mirror assembly in the event of an impact with the mirror housing, auto manufacturers have designed mirror assemblies that fold or break-away about the mounting bracket under such an impact. This is achieved by pivotally mounting a portion of the assembly to the mounting bracket on a pivot member, which is formed or provided on the bracket. A plurality of detent assemblies releasably engage the movable portion with the mounting bracket under normal loading conditions but release the engagement to permit the movable portion to pivot on the mounting bracket when the assembly is impacted by a force having sufficient magnitude. The detent assemblies are urged into this releasable engagement by a coil spring, which is supported by the pivot member. In order to pivot the assembly about the bracket and disengage the detent assemblies, a force is required which has sufficient magnitude to compress the spring.
However, these conventional break-away devices consume a significant amount of space in the mirror assembly and often dictate or limit the styling of the mirror assembly. Furthermore, when actuated to fold, the detent assemblies, which are rigidly formed and fixed in relation to the bracket and housing, induce a separating movement between the movable portion and the bracket when the housing is pivoted to its folded position. In addition, in order to function, the contact between the movable portion and the bracket is effectively limited to the detent assemblies. As a result, the vibration performance of these mirror assemblies is not optimized and these rearview mirror assemblies tend to exhibit reduced dampening performance.
The assembly process for these conventional break-away mirror assemblies is complicated requiring the spring and the spring retainer to be assembled from the top of the mirror. In addition, because more and more exterior rearview mirror assemblies incorporate electrical components, wiring of these components has complicated the mirror assembly process and has until recently been achieved by passing the wiring through the pivot joint followed by the termination of the wires. As a result, the termination of each wire has been completed during the installation of the mirror. More recently, however, such as described in U.S. patent application entitled xe2x80x9cMIRROR ACTUATOR ELECTRICAL CONNECTORxe2x80x9d, filed Jan. 11, 1999, Ser. No. 09/228,348, now U.S. Pat. No. 6,213,612, which is herein incorporated by reference in its entirety, a wire manifold or coupler has been designed that permits the wires to be terminated in the coupler before assembly of the mirror assembly, with the coupler configured so that it can be fed through the pivot member during the assembly of the mirror to substantially improve the efficiency and accuracy of the mirror assembly process. As the number of electrical components in the mirror assembly increase, however, demands on the size of the coupler similarly increase.
Consequently, there is a need for break-away exterior rearview mirror assembly that offers a simplified break-away mechanism that consumes less space than conventional break-away mechanisms while at the same time providing improved vibration characteristics and, further, providing a simplified assembly process.
Accordingly, the present invention provides an improved exterior rearview mirror assembly, especially suited for mounting on a vehicle. The exterior rearview mirror assembly includes a movable portion that is pivotally mounted to the vehicle by a fixed portion, such as a mounting bracket, and is adapted to break-away from a normal operating position (in which the movable portion is extended from the vehicle and provides a rearward filed of view to the occupant or occupants of the vehicle) to a folded position about the fixed portion closer to or adjacent the vehicle when the mirror assembly strikes or is struck by an object. The break-away function is provided by a resilient element, preferably a spring element, such as a spring, (and with a corresponding engagement element provided on the mirror assembly for cooperation with the engagement element provided on the resilient element) that incorporates at least one engagement element into the body of the resilient element, such as in a body of a spring, and, as a result, provides an engagement element (such as a detent or indent) that flexes and, therefore, does not induce a separating motion between the movable portion and the fixed portion when the movable portion is folded about the bracket. As a result, the bearing of contact the movable portion and the fixed portion may be varied from conventional break-away mirror designs to increase the dampening performance of the mirror.
According to one form of the invention, a break-away vehicle exterior rearview mirror system includes an exterior rearview mirror assembly. The exterior rearview mirror assembly includes a movable portion having a reflective element housed in the movable portion and a fixed portion adapted for mounting the movable portion to a vehicle. The exterior rearview mirror assembly further includes a pivot member, with the movable portion being pivotally mounted to the fixed portion by the pivot member for pivoting about a pivot axis for moving from a normal operating position to a break-away position. The fixed portion includes a first engagement element, and the movable portion includes a second engagement element. One of the movable portion and the fixed portion generates a resilient force, which urges the first and second engagement elements into releasable engagement with each other to thereby engage the movable portion with the fixed potion about the pivot axis. The second engagement element of the movable portion releases from engagement with the first engagement element of the fixed portion to permit the movable portion to pivot about the pivot axis when an external force having a sufficient magnitude is applied to the movable portion to overcome the resilient force. One of the engagement elements flexing when the external force is applied to the movable portion.
In one aspect, the movable portion includes the pivot member, with the movable portion and the pivot member pivoting about the pivot axis when the force is applied to the movable portion. In further aspects, the movable portion includes an actuator for adjusting the position of the reflective element in the movable portion and an actuator bracket which supports the actuator. In yet a further aspect, the actuator bracket includes the pivot member.
In another aspect, the resilient force is applied by a resilient member which includes one of the engagement elements. For example, the resilient member preferably comprises a spring and, more preferably, a plate spring. In further aspects, the resilient member is mounted to the pivot member and, preferably, coupled to the pivot member so that the resilient member rotates with or remains stationary with the pivot member. In yet further aspects, the resilient member includes at least two radially extending arms, with each of the arms including an engagement member.
In another form of the invention, a break-away vehicle exterior rearview mirror system includes an exterior rearview mirror assembly, which includes a movable portion and a fixed portion. The movable portion includes a reflective element, an actuator, and an actuator bracket, with the actuator providing adjustment of an orientation of the reflective element in the movable portion, and the actuator bracket supporting the actuator. The fixed portion is adapted to mount to a vehicle. One of the actuator bracket and fixed portion includes a pivot member, with movable portion being pivotally mounted to the fixed portion for pivoting about a pivot axis by the pivot member. A resilient member is mounted to the pivot member and releasably engages either the actuator bracket or the fixed portion, which engagement is released when an external force having sufficient magnitude to overcome the resilient force of the resilient member is applied to the movable portion whereby the movable portion pivots about the pivot axis to move between a normal operating position and a folded break-away position.
In one aspect, the actuator bracket includes the pivot member, with the movable portion and the pivot member pivoting about the pivot axis when the external force is applied.
In further aspects, the resilient member includes at least one of a detent or an indent, which releasably engages the fixed portion. In preferred form, the fixed portion includes an indent, with the resilient member including a detent, which releasably engages the indent of the fixed portion and disengages from the indent when the external force is applied to the movable portion.
In preferred form, the resilient member comprises a plate spring and, preferably, includes a central portion having a central opening and a plurality of radial portions extending outwardly from the central portion. Each of the radial portions includes a detent. In further aspects, the fixed portion includes an annular wall, with the annular wall having a plurality of indents which are releasably engaged by the detents of the resilient member to releasably engage the fixed portion. In yet further aspects, the resilient member includes an annular rim at the central opening, which seats the resilient member on the pivot member.
In yet another form of the invention, a break-away vehicle exterior rearview mirror system includes an exterior rearview mirror assembly. The exterior rearview mirror assembly includes a movable portion and a fixed portion. The movable portion includes a reflective element housed in the movable portion and a pivot member. The fixed portion is adapted for mounting the movable portion to a vehicle, with movable portion being pivotally mounted to the fixed portion by the pivot member for pivoting about a pivot axis. A resilient member is mounted to the pivot member and applies a resilient force to urge the movable portion into a releasable engagement with the fixed portion and releases the engagement when an external force having sufficient magnitude to overcome the resilient force of the resilient member is applied to the movable portion whereby the movable portion pivots about the pivot axis between a normal operating position and a folded break-away position.
In one aspect, the resilient member includes at least one engagement element for releasably engaging the fixed portion. In further aspects, the engagement element flexes when an external force is applied to the movable portion whereby the movable portion and the fixed portion maintain their relative spacing when the movable portion is pivoted about the pivot axis.
As will be understood, the exterior rearview mirror system of the present invention provides numerous advantages over prior known mirror assemblies. The rearview mirror system provides a break-away mechanism, which protects the mirror assembly from damage in the event that the mirror assembly is impacted during the use of the vehicle, with a break-away mechanism which consumes less space than conventional break-away mechanisms. With the reduced space, the height of the pivot member can be reduced thus increasing the size of the available pathway from the mounting bracket into the mirror assembly to ease wiring of the ever increasing number of electrical components within the mirror assembly. In addition, the exterior rearview mirror system exhibits increased dampening and, therefore, also exhibits improved vibration characteristics while also providing a consistent stable, break-away force over the life of the mirror assembly.
These and other objects, advantages, purposes, and features of the invention will become more apparent from the study of the following description taken in conjunction with the drawings.